1838 is often listed as the year for the invention of the telegraph. This was when Samuel Morse first successfully tested his electrical telegraphy device in the US. Cooke and Wheatstone listed a patent in England for a similar device in 1837 as an alarm system. In 1836, David Alter, a US scientist, demonstrated a telegraph in Pennsylvania. In 1832, the German Baron Schilling invented a telegraphy transmitting device which seems to have inspired Cooke. In 1831, Gauss and Weber collaborated and then in 1833 designed a telegraphy device that sent communications data using four amplitudes of a galvanometer needle.

The credit for inventing the telegraph seems to have been given to Morse in part because of the widespread adoption of the telegraphy code system developed by his assistant, Alfred Vail, which is now known as Morse Code. The first commercial telegraph line in the US connected Lancaster, PA and Harrisburg, PA in 1845. The first transcontinental telegraph line in the US was established in 1861 when an existing network on the east coast was connected to another network in California by a link in Salt Lake City. The pony express stopped operations two days later and became obsolete. The first transatlantic telegraph cable was completed in 1866. In 1876, Elisha Gray and Alexander Bell were competing to create “improved telegraphy” and the telephone was created. In 2006, Western Union ended their telegraph messaging service.